Change over



Jul 29, 1930. L, D, STRONG "1,171,591

CHANGEOVER Filed Dec. 8, 1927 2 smug-sheet 2 Patented July 29, 1930PATENT OFFICE LAWRENCE D. STRONG, 01 M AYWOOD, ILLINOIS CHAN GE OVERApplicatian filed December 8, 1927. Serial No. 238,559.

This invention relates to change-overs or devices for cutting off thelight from projecting machines, such as moving picture machines,stereopticons and effect machines. While my improved change-over devicemay be used with various types of projecting machines, it is articularlyadapted for use in connection with projecting machines having lowintensity lamps with wider beams of light distribution and largerlenses. On account of the larger sized light beams, it is more difliculttoproperly cut oil the beam without undue distortion or objectionableeffects on the screen. The present invention is designed to properlyhandle such beams and not only provides means for cutting them oilinstantaneously in a satisfactory manner but also provides means wherebit may be operated by hand to give a slow iris fade out when deslred.

Among the objects of this invention are to provide an improvedchange-over device of the character indicated; to provide a changeoverdevice having a plurality of coacting radially-swingin shutters withelectrically operated means or opening and closing the same; to providea comblned electric and hand operated change-over device of thischaracter; to provide a change-over with electric operating means andmeans whereby the current will be automatically cut off from theoperatingmeans immediately after op-' eration; to provide a change-overhaving a plurality of shutter blades with solenoids for operating thesame and having a switch arranged to cut off the electricity immediatelyafter eachoperation so that it is impossible to burn out the coils; toprovide an improved switch for devices of this character; and to providesuch other advantages and novel fi eatures as will inafter.

In the accompanying drawings illustratbe described more fully hereingthis invention,

igure 1 is a 'front view with the cover removed;

Figure 2 is a sectional view taken on the line 2'2 of Iigure 1;

Figure 3 is a sectional view taken on the line 3-3 of Figure 1; and

Figure 4 is a diagrammatic view showing the clrcuits. In the particularform of the device as shown in these drawings, the operating mechanismis enclosed in a box or casing 6 which is provided with a cover 7 andwhich may be supported in a port opening in the front Wall of the boothin any suitable manner or in some instances, if desired, may be mounteddirectly in front of the projecting machine.

The front wall 8 has an opening 9 which is provided with an inwardlyprojecting flange 10 and the cover has a hole 11 which registers withthe hole 9 or is in alignment therewith and has an inwardly projectingflange 12. In one commercial form as now constructed, these openings arefive inches in diameter which is sufliciently large to pass all lightrays from the projectors, stereopticons and effect machines now incommon use.

The shutters 13, 14 and 15 are preferably of the iris type and arepivoted on studs 16, 17 and 18, which engage with lugs around the flange10. The blades are held in spaced relation so that they will clear eachother by means of sleeves 19, 20 and 21 which fit over the studs and areof different heights, as shown in Figure 2. These sleeves are reducedadjacent to the flange 10 to form bearings for the shutter operatingring 22 WhlCll is rotatably mounted thereon. This ring has pins 23 forengagement with slots 24 in the shutters for swinging the same, thearrangement being such that as the ring is movedan an anti-clockwisedirection, as shown in Figure 1, the shutters will be swung in to closethe opening, and then as the ring is moved in the opposite direction,the-shutters will be swung out to open position, as shown 1n this Thering 22 has a handle 25 which extends outwardl through a slot 26 in theside of the casing wli ereby the 'device may be manually operated. Thering 22 is preferably provided with an overthrow spring WhlCh tends tothrow it to complete open or complete closed position. In thearrangement shown, the spring 27 is attached at one end to a pin 28 onthe frame and at the other end to the free end of an arm 28 which ispivoted at 29 to the frame or casing. The outer or free end of the arm28 is provided with a slot 30 for receiving a pin 31 on the arm orhandle 25. As shown in Figure 1, the spring is past dead center andtends to hold theshutters in open position. When the ring is swung inthe opposite direction to close the shutters, the spring will pass thedead center and tend to hold the parts in closed position.

The change-over is electrically operated by solenoids 32 and 33 whichare rigidly Secured in-the bottom of the box or casing 6. The plunger 34of the solenoid 32 is connected by a link 35 with a projection 36 on thering 22. The plunger 37 of the solenoid 33 is connected'by a link 38with the arm 25. When current is supplied to the solenoid 33 its plungerwill be drawn in, thereby swinging the device to open position, as shownin Figure 1, and when current is supplied to the solenoid 32, itsplunger will be drawn in, thereby swinging the parts to closed position.l

5' As these solenoids require a comparatively 5 heavy current to operatethem satisfactorily,

I have provided a novel device for automatically cutting 0a the currentfrom the respective solenoids after they have been actuated so that itis impossible for the operator to burn out the solenoids by permittingcurrent to flow therethrough for too long a period. While the circuit isthus broken to the operating solenoid, it is also closed to the othersolenoid so that it will be in condition for operation. This isaccomplished by means of a double switch which is actuated by theshutter opening and closing mechanism. In the particular arrangementshown, the ring 22 is provided with an arm 39 formed of insulatingmaterial and carrying a contact pin 40 which is adapted to engage attimes withitwo sets of switch blades 41, 42 and 43, 44. The bent ends ofthe blades 41 and 42 engage with sockets or recesses 45 and 46 incontact brackets 47 and'48 which are carried on a block of insulating-material 49 mounted in a chamber 50 at the top of the box 6. The bladesare resiliently held in engaging position by means of bolts 51 and 52and springs 53 and 54, as will be readily understood from Figure 1. Theswitch blades 43 and 44 are similarly connected with contact brackets 55and 56 also secured to the block 49. The forward ends of the blades arebent outwardly to facilitate the engagement of the contact 40 therewithand by bending these out more or less the length of time that current issupplied to the respective solenoids may be regulated in order toincrease or decrease the power, and consequently the speed of operation.The circuit for the solenoid is from a contact or binding post 5'7 to acommon wire 58 to switch blade 41 and 43, contact or binding post 59through wire 60, solenoid 32, wire 61 to switch blade 44. From terminalor contact 62 through wire 63, solenoid 33, wire 64 to switch blade 42.The contacts or terminals 57, 59 and 62 are connected with the linewires 65,66 and 67 from any suitable source of supply, and the circuitsto the respective solenoids may be openedand closed by a switch 68. Whenthe switch 68 is'closed to supply current to the wires 65 and 66, thesolenoid 32 will be I 39 will carry the contact 40 away from the openingthe cirblades 43 and 44, thereb cuit to the solenoid 32 an stopping thesu ply of current'thereto. This will usua y occur at about the time thespring 27 passes the dead center and the spring together with theinertia of the arts will insure the closing of the shutter. s the arm 39continues its movement, the contact 40 will be brought into engagementwith the blades 41 and 42, there by closing the circuit to the solenoid33 so that it will be in conditionto operate to open the shutters whenthe switch 68 is operated to supply current to the wires 65 and 67 thecircuit for this operation being wire 65, terminal 57, wire 58, switchblade 41, contact 40, switch blade 42, wire 64. solenoid 33, wire 63,terminal 62 and wire 67.

Usually a numberof these change-overs are used in a single operatingbooth and the switches, such as indicated by the switch 68 are 13006operated, but on account of the automatic circuit breaking mechanismjust described, no damage will result even if the switch 68 is keptclosed for an indefinite period.

Myeimproved change-over mayfof course,-

be made in various sizes or styles for different conditions and changesmay be made in the details "of construction without departing from thescope of this invention; there 'fore I do not wish to be limited to theexact arrangement herein shown and described ex-. cept as set forth inthe following claims, in i which I claim: 1

A change-over comprising a frame having an opening therethrough, shutterblades for opening and closing said openin an electro-responsive devicefor opening t e shutters, an electro-responsive device for closing theshutters, and means for automatically opening the circuits to therespective devices when? they have been actuated.

2. In a change-over, the combination of a plurality of shutters, meansfor actuating the shuttersto open and closethe same, a solenoidconnected with the actuating. means for moving it toiop'en the shutters,a second solenoid connected with the actuating means for moving it toclose the shutters, electric circuits for said solenoids, and switchesactuated by the opening and closing means for opening the circuits tothe respective solenoids.

3. A change-over comprising a casing having an opening therethrough,'aplurality of shutters pivoted adjacent to the opening, a ring, pins onsaid ring engaging with slots in the shutters for swinging the shutters,a handle projecting from said ring, a closing solenoid connected withthe ring, an opena 4. A change-over comprising a casing having anopening therethrough, a plurality of shutters pivoted adjacent to theopening and adapted to open and close the same, a ring rotatably mountedadjacent to the shutters, means connecting the ringwith the shutters andadapted to swing the shutters as the ring is rotated, a handleprojecting from the ring through the casing, overthrow spring mechanismoperatively connected with the casing and handle and tending to throwthe ring to open or closed position respectively, a sole noid for movingthe ring to open position, a link connecting the solenoid plunger withthe ring, a second solenoid for moving the ring to closed position, alink connecting the Y plunger of this solenoid with the ring, an

electric circuit for the firstnamed solenoid including a pair of switchblades, an electric circuit for the second named solenoid also includinga pair of switch blades, and a contact member carried by said ring andadapted to engage with the respective pairs of switch blades to open andclose the circuits to the solenoids, substantially as described.

5. An electric change-over device of the character set forth havingmultiple blade iris type shutters, solenoids operatively connected withsaid shutters for actuating the same, means whereby the current isautomatically 1 cut off from the respective solenoids immediately afteroperation, and means tending to hold t e shutters in open and closedpositions,

respectively. 7

LAWRENCE D. STRONG. I

